Phenotype analysis of 11 fetuses with 22q11.2 microduplication diagnosed prenatally / 中华全科医师杂志

Objective:To analyze the clinical phynotypes of fetuses with 22q11.2 microduplications.Method:Eleven fetuses were diagnosed with 22q11.2 microduplications among 2 969 cases who underwent prenatal chromosomal microarray analysis from January 2016 to February 2020. The phenotypes, indications for invasive prenatal diagnosis, genetic results, pregnancy outcomes and postnatal clinical presentation were analyzed.Results:There were 6 cases diagnosed with classic 3.0 Mb microduplication (DiGeorge and velocardiofacial syndromes, DGS/VCFS) in the 22q11.2, 1 case with 1.5 Mb proximal microduplication and 4 cases with distal small segment microduplication (E-H). Out of 11 fetuses with 22q11.2 microduplications,7 cases were inherited, 2 cases was de novo and data were not available for 2 cases. Vicular septal defect and anencephalu were diagnosed by ultrasonography in 2 cases,fetal growth restriction was diagnosed in 2 cases,no any abnormalities were found in remaining 7 cases. Seven cases(3 cases of classic 3.0 Mb microduplication, 1 case of proximal microduplication and 3 cases of distal small segment microduplication) were delivered at full-term;and pregnancy was terminated in 4 cases. Seven infants were followed up after birth, 4 infants were normal, 3 showed abnormal phenotypes.Conclusion:The clinical phenotypes after birth of fetuses with 22q11.2 microduplication are diverse. Prenatal genetic counseling is necessary,so that pregnant women and their families can fully understand the possible clinical phenotypes and make informed choices.

Riesgo de Esquizofrenia y Síndrome Deleción 22Q11. 2 / RIsk of schizophrenia and 22q11. 2 deletion syndrome

INTRODUCCIÓN. La deleción 22q11.2 es una alteración cromosómica muy frecuente, en la cual un 60% de los afectados presenta patologías neuropsiquiátricas. Determinar si existe asociación entre el síndrome de deleción 22q11.2 (SD22q11.2) y patologías como la esquizofrenia (EQZ), ofrece una oportunidad para la intervención temprana, y seguimiento de personas con este síndrome. OBJETIVO. El objetivo del presente trabajo es determinar si existe mayor riesgo de EQZ en pacientes con síndrome deleción 22q11.2. MÉTODOS. Se realizó una búsqueda bibliográfica sistemática de publicaciones con fecha de 1990 a 2020. Las búsquedas se realizaron en PubMed y en la base de datos Cochrane. En total, se evaluaron 19 estudios, de los que se consideraron elegibles diez publicaciones para el análisis, lo que corresponde a 824 participantes. RESULTADOS. El riesgo de presentar EQZ en un individuo con SD22q11.2 es de 20-25%, en comparación al 1% de la población general. CONCLUSIONES. El riesgo para un individuo con SD22q11.2 de presentar EQZ se encuentra bien establecido. Considerar este riesgo podría ayudar a un adecuado seguimiento y una intervención temprana.

INTRODUCTION. 22q11.2 deletion syndrome is a very common chromosomal abnormality, in which 60% of those affected have neuropsychiatric disorders. Determining if there is an association between 22q11.2 deletion syndrome (22q11.2DS) and disorders such as schizophrenia (SCZ) offers an opportunity for early intervention and follow-up of people with this syndrome. OBJECTIVE. The objective of this study is to determine if there is a greater risk of SCZ in patients with 22q11.2 deletion syndrome. METHODS. A systematic review was performed for publications dated 1990 to 2020. The strategy was to search in PubMed and Cochrane databases for specific MeSH terms. In total, 19 studies were reviewed, of which 10 publications were eligible for analysis, corresponding to 824 participants. RESULTS. The risk of presenting SCZ in an individual with 22q11.2DS is 20-25%, compared to 1% in the general population.CONCLUSIONS. The risk of presenting SCZ in an individual with 22q11.2DS is well established. Considering this risk could help with adequate follow-up and early intervention.

One case of misdiagnosis of 22q11.2 deletion syndrome with ovarian mixed germ cell tumor / 中华内分泌代谢杂志

Idiopathic hypoparathyroidism is a rare endocrine disease. It is often manifested as neuropsychiatric symptoms, especially epileptic seizures. Thus, it is easy to be misdiagnosed as primary epilepsy. The following case report details the diagnosis of a 17-year-old girl who had been misdiagnosed as primary epilepsy for a long time. She was found hypoparathyroidism during the hospitalization for the operation of ovarian mixed germ cell tumor. After whole exome sequencing, she was ultimately diagnosed as 22q11.2 deletion syndrome. This case suggested that clinicians should be aware of the possibility of hypoparathyroidism in adolescent epilepsy, especially hereditary hypoparathyroidism. At the same time, the possible high risk of tumors should also be considered in hereditary hypoparathyroidism.

Research progress on mechanism of TBX1 gene affecting phenotype of 22q11.2 microdeletion syndrome / 医学研究生学报

22q11.2 microdeletion syndrome is a genetic syndrome caused by the deletion of 22q11.21-q11.23 in the proximal long arm microfragment of chromosome 22 for human. TBX1 belongs to the T-box family and is located in 22q11.2 of chromosome. Studies have shown that haploinsufficiency of TBX1 is the main cause of 22q11.2 microdeletion syndrome, which is of great significance for the appearance of its phenotype. Therefore, this paper reviews the research progress of TBX1 in the mechanism of cardiac disease, pulmonary artery phenotype, thymus development, pharyngeal and palatal development, lymphatic formation, and low proliferation of parathyroid tumors.

Research progress on mechanism of TBX1 gene affecting phenotype of 22q11.2 microdeletion syndrome / 医学研究生学报

22q11.2 microdeletion syndrome is a genetic syndrome caused by the deletion of 22q11.21-q11.23 in the proximal long arm microfragment of chromosome 22 for human. TBX1 belongs to the T-box family and is located in 22q11.2 of chromosome. Studies have shown that haploinsufficiency of TBX1 is the main cause of 22q11.2 microdeletion syndrome, which is of great significance for the appearance of its phenotype. Therefore, this paper reviews the research progress of TBX1 in the mechanism of cardiac disease, pulmonary artery phenotype, thymus development, pharyngeal and palatal development, lymphatic formation, and low proliferation of parathyroid tumors.

Síndrome de DiGeorge/velocardiofacial: reporte de un caso / DiGeorge/velocardiofacial syndrome: a case report

El síndrome de DiGeorge, también conocido como síndrome velocardiofacial o síndrome de deleción 22q11, se caracteriza por la ausencia congénita del timo y la glándula paratiroides. La tríada clásica de este trastorno es cardiopatía congénita, endocrinopatía con hipocalcemia e inmunodeficiencia primaria. Sin embargo, el síndrome puede exhibir múltiples alteraciones y manifestaciones clínicas pleiotrópicas que, a menudo, resultan en dismorfismo facial y alteraciones en el paladar. Clínicamente se evidencia mayor susceptibilidad a infecciones respiratorias o gastrointestinales recurrentes y, en los casos de aplasia tímica, se requiere tratamiento con antibióticos profilácticos y trasplante tímico, mientras que en los demás se hace manejo expectante. En este manuscrito se presenta el caso de un paciente masculino de 18 meses de edad, remitido al servicio de genética por presentar diversas alteraciones fenotípicas. Se describe el proceso mediante el cual se llegó al diagnóstico de síndrome de DiGeorge, a su manejo y pronóstico, y se hace una breve revisión de la literatura

DiGeorge syndrome, also known as velocardiofacial syndrome or 22q11 deletion syndrome, is characterized by the congenital absence of the thymus and the parathyroid gland. The classic triad of this disorder is congenital heart disease, endocrinopathy with hypocalcemia and primary immunodeficiency. However, the syndrome may exhibit multiple pleotropic abnormalities and clinical manifestations that often result in facial dysmorphism and changes in the palate. Clinically, a high susceptibility to recurrent respiratory or gastrointestinal infections is observed. In cases of thymic aplasia, treatment with prophylactic antibiotics and thymic transplantation is necessary, while in others, expectant management is used. This manuscript presents the case of an 18-month old male patient, referred to the genetics service due to several phenotypic alterations. The process by which the Di- George syndrome diagnosis, management and prognosis was reached, as well as a brief review of the literature, are presented.

Cardiopatías congénitas asociadas a la microdeleción 22q11. 2, en un hospital pediátrico / Congenital heart defects associated with a 22q11. 2 microdeletion at a pediatric hospital

Introducción: El síndrome de deleción 22q11.2, también llamado síndrome Velo-Cardio-Facial (VCFS/del22q11.2) o síndrome de DiGeorge, es una entidad causada por una anomalía cromosómica, deleción en la región q11.2 (brazo largo) del cromosoma 22. Se trata de una enfermedad multisistémica de expresión variable que afecta el aparato cardiovascular, la inmunidad, las funciones endocrinológicas, la cavidad oral, el desarrollo neurocognitivo, con una expresión facial particular. La prevalencia estimada es de 1:2000/4000. Objetivos: Identificar y describir las cardiopatías congénitas más frecuentemente asociadas a pacientes con síndrome de microdeleción 22q11.2. Materiales y métodos: Estudio descriptivo, transversal y retrospectivo que analiza los pacientes con diagnóstico de microdeleción 22q11.2 atendidos en el Hospital Garrahan desde Octubre de 1998 hasta Febrero 2018. El criterio diagnóstico fueron signos clínicos compatibles y la presencia de la microdeleción 22q11.2 por técnica de FISH o MLPA. Resultados: Población: 321 pacientes, 151 Femeninos (47%) 170 Masculinos (53%). Rango etario: 0 a 197 meses (1 día a 16,4 años). Mediana de edad al diagnóstico clínico: 31 meses. El 74,4% (239/321) de los pacientes evaluados con microdeleción 22q11.2 tuvieron cardiopatías congénitas asociadas a facies peculiar. Las cardiopatías congénitas más frecuentemente asociadas fueron conotroncales. De los pacientes con cardiopatías congénitas el 68,6% requirió cirugía cardiovascular. Fallecieron 24 pacientes (10%) con cardiopatías congénitas asociadas y en el 93% la causa de muerte estuvo relacionada a la afección cardiológica. Conclusiones: Los pacientes con microdeleción 22q11.2 se asocian con un alto porcentaje de cardiopatías congénitas, la gran mayoría son complejas (conotroncales) y requieren resolución quirúrgica en los primeros años de vida. Es de vital importancia la evaluación multidisciplinaria de este grupo especial de pacientes con cardiopatía asociada a otras alteraciones extra cardíacas para el diagnóstico precoz y tratamiento oportuno (AU)

Introduction: 22q11.2 deletion syndrome, also called velocardiofacial syndrome (VCFS/del22q11.2) or DiGeorge syndrome, is a condition caused by chromosomal abnormality, a deletion in the q11.2 region (long arm) of chromosome 22. VCFS is a multisystem disease of variable expression that affects the cardiovascular, immune, and endocrine systems, the oral cavity, neurocognitive development, and is associated with specific facial features. The estimated prevalence is 1:2000/4000. Objectives: To identify and describe the most common congenital heart defects associated with 22q11.2 micro-deletion syndrome. Materials and methods: Descriptive, cross-sectional, and retrospective study analyzing patients diagnosed with a 22q11.2 microdeletion seen at Garrahan Hospital from October 1998 to February 2018. Diagnostic criteria were compatible clinical signs and the presence of a 22q11.2 microdeletion identified by FISH or MLPA. Results: Population: 321 patients, 151 female (47%) and 170 Male (53%). Age range: 0 to 197 months (1 day to 16.4 years). Median age at clinical diagnosis: 31 months. Overall, 74.4% (239/321) of patients with a 22q11.2 microdeletion had congenital heart defects associated with a peculiar facies. The most commonly associated congenital heart defects were conotruncal. Of the patients with congenital heart defects, 68.6% required cardiovascular surgery. Of the patients with congenital heart defects 24 patients died (10%) and in 93% the cause of death was related to the heart disease (p 0.002). Conclusions: A high percentage of patients with a 22q11.2 microdeletion have congenital heart defects, which are complex (conotruncal) in the majority, requiring surgical treatment in the first years of life. Multidisciplinary evaluation of this special group of patients with heart defects associated with other extracardiac disorders is essential for an early diagnosis and timely treatment (AU)

Consideraciones anestésicas en pacientes con microdeleción del cromosoma 22q11 / Anesthetic issues in patients mycrodeletion syndrome produced by the deletion of chromosome 22q11

The syndrome produced by the deletion of chromosome 22q11 corresponds to a pattern of anomalies that occurs when a specific region of chromosome 22 is lost, specifically called 22q11.2. This microdeletion corresponds to the most frequent chromosomal alteration in humans, which has a prevalence of 1 per 4,000 live births. This includes a great variety of phenotypes, many of them subclinical, among which the Di George syndrome and the Velocardiofacial syndrome stand out. The main cause of mortality is of cardiac origin. Embryologically, this microdeletion is associated with alterations in the differentiation and migration of the pharyngeal system, with consequent craniofacial, cardiac, airway, thymus and parathyroid alterations, among others. In this sense, these patients present a higher risk of complications such as inmunodeficiency, hypocalcemia and hemorrhagic risk. From the surgical and anesthetic point of view, they can present cardiopathies of greater complexity of correction, which in some cases is also related to anatomical airway alterations which can constitute an important challenge when operating this type of patients. Considering the above, there is an increase in perioperative risk which could increase mortality. The objective of this review is to present the characteristics and behavior of this group of patients in the correction of their heart diseases, so that they are known by the anesthesiologists who work in the cardiovascular area.

El síndrome de microdeleción 22q11 corresponde a un patrón de anomalías que se produce al perderse una región específica del cromosoma 22, específicamente llamada 22q11.2. Esta microdeleción corresponde a la alteración genética más frecuente en humanos la cual tiene una prevalencia de 1 cada 4.000 recién nacidos vivos. Incluye una gran variedad de fenotipos, muchos de ellos subclínicos, entre los que destaca el síndrome Di George y el síndrome Velocardiofacial. La principal causa de mortalidad es de origen cardíaco. Embriológicamente la microdeleción se asocia a alteraciones en diferenciación y migración del aparato faríngeo, con las consiguientes alteraciones cráneo-faciales, cardíacas, de vía aérea, timo y paratiroides, entre otras. En ese sentido, presentan mayor frecuencia de complicaciones tales como infecciones, hipocalcemia y riesgo hemorrágico. Desde el punto de vista quirúrgico y anestésico pueden presentar cardiopatías de mayor complejidad de corrección, asociado o no a alteraciones anatómicas en vía aérea lo que puede constituir un importante desafío al momento de intervenir. Lo anterior aumenta el riesgo perioperatorio, lo que podría derivar en aumento de la mortalidad. El objetivo de esta revisión es presentar las características y comportamiento de este grupo de pacientes en la corrección de sus cardiopatías, de modo que sean un aporte para los anestesiólogos que se desempeñan en el área cardiovascular.

22q11.2 deletion detected by in situ hybridization in Mexican patients with velocardiofacial syndrome-like features / Deleción 22q11.2 detectada por hibridación in situ en pacientes mexicanos con características clínicas similares al síndrome velocardiofacial

Abstract Introduction: Deletion 22q11.2 occurs in 1:4,000-1:6,000 live births while 10p13p14 deletion is found in 1:200,000 newborns. Both deletions have similar clinical features such as congenital heart disease and immunological anomalies. Objective: We looked for a 22q11.2 deletion in Mexican patients with craniofacial dysmorphisms suggestive of DiGeorge or velocardiofacial syndromes and at least one major phenotypic feature (cardiac anomaly, immune deficiency, palatal defects or development delay). Methods: A prospective study of 39 patients recruited in 2012-2015 at the Instituto Mexicano del Seguro Social at Guadalajara, Mexico. The patients with velocardiofacial syndrome-like features or a confirmed tetralogy of Fallot (TOF) or complex cardiopathy were studied by G-banding and fluorescence in situ hybridization (FISH) with a dual TUPLE1(HIRA)/ARSA or TUPLE1(22q11)/22q13(SHANK3) probe, six patients without the 22q11.2 deletion (arbitrarily selected) were tested with the dual DiGeorge II (10p14)/D10Z1 probe. Results: Twenty-two patients (7 males and 15 females) had the 22q11.2 deletion and 17/39 did not have it; no patient had a 10p loss. Among the 22 deleted patients, 19 had congenital heart disease (mostly TOF). Twelve patients without deletion had heart defects such as TOF (4/12), isolate ventricular septal defect (2/12) or other disorders (6/12). Conclusion: In our small sample about ~56% of the patients, regardless of the clinical diagnosis, had the expected 22q11.2 deletion. We remark the importance of early cytogenetic diagnosis in order to achieve a proper integral management of the patients and their families.

Resumen Introducción: La deleción 22q11.2 ocurre con una frecuencia de 1:4,000-1:6,000 nacidos vivos, mientras que la deleción 10p13p14 es detectada en 1:200,000 recién nacidos. Ambas deleciones comparten características clínicas similares tales como defectos cardiacos congénitos y anomalías inmunológicas. Objetivo: Identificar la deleción 22q11.2 en pacientes mexicanos con dismorfismo craneofacial sugestivo de síndrome DiGeorge o velocardiofacial y por lo menos con una característica clínica mayor (anomalía cardiaca, deficiencia inmunológica, defectos en paladar o retardo en el desarrollo) Métodos: Estudio prospectivo de 39 pacientes captados entre 2012-2015 en el Instituto Mexicano del Seguro Social en Guadalajara, México. Los pacientes con características clínicas sugerentes de síndrome velocardiofacial o diagnostico confirmado de tetralogía de Fallot (TOF) o cardiopatía compleja fueron estudiados por bandas G y por hibridación in situ fluorescente (FISH) con una sonda dual TUPLE1(HIRA)/ARSA o TUPLE1(22q11)/22q13(SHANK3), seis pacientes sin la deleción 22q11.2 (seleccionados arbitrariamente) fueron estudiados con la sonda dual DiGeorge II (10p14)/D10Z1. Resultados: Veintidós pacientes (7 hombres y 15 mujeres) tuvieron la deleción 22q11.2 y 17/39 no la tuvieron, ningún paciente tuvo la pérdida de 10p. Entre los 22 pacientes delecionados, 19 tuvieron defecto cardiaco congénito (principalmente TOF). Doce pacientes sin la deleción tuvieron defectos cardiacos congénitos como TOF (4/12), defecto del septo ventricular aislado (2/12) y otros trastornos cardiacos (6/12). Conclusión: En nuestra pequeña muestra, alrededor de ~56% de los pacientes, independientemente de su diagnostico clínico, tuvieron la deleción 22q11.2 esperada. Resaltamos la importancia del diagnóstico citogenético temprano para determinar un apropiado manejo integral para el paciente y sus familiares.

22q11.2 deletion syndrome / 中华实用儿科临床杂志

22q11.2 deletion syndrome is the commonest chromosome deletion syndrome.Most patients with DiGeorge anomaly have monosomic deletions of chromosome 22q11.2.Abnormal pharyngeal arch development results in defects in the development of the parathyroid glands,thymus and conotruncal region of the heart.Defective thymus development is associated with impaired immune function." Complete" DiGeorge syndrome accounts for ＜ 0.5％ of patients with total absence of the thymus and a severe T cell immunodeficiency.Most patients with partial defects have variable T cell deficiency.There is a wide phenotypic spectrum including speech delay,neuropsychiatric disorders and otolaryngological disorders.These patients are at increased risk of a variety of autoimmune diseases.Severe cases need thymus transplantation.

Genomic imbalances in syndromic congenital heart disease / Desequilíbrios genômicos na cardiopatia congênita sindrômica

Abstract Objective: To identify pathogenic genomic imbalances in patients presenting congenital heart disease (CHD) with extra cardiac anomalies and exclusion of 22q11.2 deletion syndrome (22q11.2 DS). Methods: 78 patients negative for the 22q11.2 deletion, previously screened by fluorescence in situ hybridization (FISH) and/or multiplex ligation probe amplification (MLPA) were tested by chromosomal microarray analysis (CMA). Results: Clinically significant copy number variations (CNVs ≥300 kb) were identified in 10% (8/78) of cases. In addition, potentially relevant CNVs were detected in two cases (993 kb duplication in 15q21.1 and 706 kb duplication in 2p22.3). Genes inside the CNV regions found in this study, such as IRX4, BMPR1A, SORBS2, ID2, ROCK2, E2F6, GATA4, SOX7, SEMAD6D, FBN1, and LTPB1 are known to participate in cardiac development and could be candidate genes for CHD. Conclusion: These data showed that patients presenting CHD with extra cardiac anomalies and exclusion of 22q11.2 DS should be investigated by CMA. The present study emphasizes the possible role of CNVs in CHD.

Resumo Objetivo: Identificar desequilíbrios genômicos patogênicos em pacientes que apresentam cardiopatias congênitas (CC) e anomalias extracardíacas e exclusão da síndrome de deleção 22q11.2 (SD22q11.2). Métodos: Foram avaliados por microarray cromossômico (CMA) 78 pacientes negativos para a deleção 22q11.2, previamente testados por hibridação in situ com fluorescência (FISH) e/ou amplificação de múltiplas sondas dependentes de ligação (MLPA). Resultados: Foram identificadas variações do número de cópias de DNA (CNVs) clinicamente significativas (≥ 300 kb) em 10% (8/78) dos casos, além de CNVs potencialmente relevantes em dois casos (duplicação de 993 kb em 15q21.1 e duplicação de 706 kb em 2p22.3). Genes envolvidos como IRX4, BMPR1A, SORBS2, ID2, ROCK2, E2F6, GATA4, SOX7, SEMAD6D, FBN1 e LTPB1 são conhecidos por atuar no desenvolvimento cardíaco e podem ser genes candidatos a CC. Conclusão: Esses dados mostram que pacientes que apresentam CC, com anomalias extracardíacas e exclusão da SD22q11.2, devem ser investigados por CMA. Ainda, este estudo enfatiza a possível função das CNVs nas CC.

Congenital imperforate anus complicated with 22q11.2 deletion syndrome:a case report and literature review / 临床儿科杂志

Objective To explore the clinical phenotype of 22q11.2 deletion syndrome with imperforate anus. Methods The clinical diagnosis and treatment of one case of 22q11.2 deletion syndrome complicated with anal atresia were retrospectively analyzed. Gene and phenotype of this disease were analyzed, and the related literature was reviewed. Results An elder male test tube infant of twins, born to a G2P2 mother were found to have special facial features, cleft palate, congenital heart disease, and imperforate anus after birth. A genome-wide microarray scan revealed 22q11.2 deletion syndrome. In related literatures, 22q11.2 deletion syndrome could be affected by TBX1 gene, histone modification, Ranbp1 gene, and even microRNA; while imperforate anus were influenced by multiple elements such as genetic, maternal, and environmental factors and multiple embryonic developments related genes could be involved in its pathogenesis. Conclusions Congenital imperforate anus and 22q11.2 deletion syndrome are mostly sporadic cases in epidemiology and are incidental accidents in development. Whether there is a common interaction factor between them needs to be further studied and defined.

Delayed diagnosis of 22q11 deletion syndrome due to late onset hypocalcemia in a 11-year-old girl with imperforated anus

Neonatal hypocalcemia and congenital heart defects has been known as the first clinical manifestation of the chromosome 22q11.2 deletion syndrome (22q11DS). However, because of its wide clinical spectrum, diagnosis of 22q11DS can be delayed in children without classic symptoms. We report the case of a girl with the history of imperforate anus but without neonatal hypocalcemia or major cardiac anomaly, who was diagnosed for 22q11DS at the age of 11 after the onset of overt hypocalcemia. She was born uneventfully from phenotypically normal Korean parents. Imperforate anus and partial cleft palate were found at birth, which were surgically repaired thereafter. There was no history of neonatal hypocalcemia, and karyotyping by GTG banding was normal. At the age of 11, hypocalcemia (serum calcium, 5.0 mg/dL) and decreased parathyroid hormone level (10.8 pg/mL) was noted when she visited our Emergency Department for fever and vomiting. The 22q11DS was suspected because of her mild mental retardation and velopharyngeal insufficiency, and a microdeletion on chromosome 22q11.2 was confirmed by fluorescence in situ hybridization. The 22q11DS should be considered in the differential diagnosis of hypocalcemia at any age because of its wide clinical spectrum.

Síndrome de deleción 22q11: bases embriológicas y algoritmo diagnóstico / 22q11 deletion syndrome: embryology and diagnostic algorithm

Resumen El síndrome de deleción 22q11 consiste en una agrupación variable de características fenotípicas secundarias a la pérdida del material genético localizado en la banda 22q11.2. El espectro de deleción del 22q11 abarca varios síndromes, antes considerados independientes pero hoy relacionados con la misma etiología, con anomalías superpuestas incluyendo el síndrome de DiGeorge y el síndrome velocardiofacial, entre otros. Se trata de un síndrome pleiotrópico incluyendo: alteraciones en los sistemas cardiaco e inmunológico, dificultades en el aprendizaje y malformaciones del paladar entre las afecciones más comunes. Se hizo una revisión de: la base embriológica de las malformaciones congénitas cardiacas, la epidemiología, la genética, la fisiopatología y los aspectos clínicos en el manejo de esta enfermedad. Dado que esta enfermedad rara es potencialmente una causa importante pero ignorada de morbimortalidad en Colombia, se propone también una estrategia para su búsqueda activa y se discuten aspectos relacionados con su diagnóstico.

Abstract The 22q11 deletion syndrome is characterized by a variable group of phenotypic features secondary to the loss of genetic material located on the band 22q11.2. Its spectrum covers multiple syndromes, previously considered independent but nowadays related to the same etiology with overlapping anomalies, including DiGeorge and velocardiofacial syndromes. It presents alterations in the immune and cardiac systems, neurodevelopment and palatal defects amongst the most common problems. This article is a review of the embryologic basis for the congenital heart defects, epidemiology, genetics, pathophysiology and clinical aspects of this disease. This is a rare disease but is a potentially underdiagnosed cause of morbidity and mortality in Colombia, for which a strategy for its active search is also proposed and diagnostic aspects are discussed.

Abordaje inmunológico del síndrome por deleción 22q11 / Immunological approaches to 22q11 deletion syndrome

El síndrome por deleción 22q11 (SD22q11) es el síndrome por deleción cromosómica más frecuente en humanos y se caracteriza por la tríada clínica que incluye cardiopatía congénita, hipocalcemia e inmunodeficiencia primaria. El 85-90% de los pacientes tienen microdeleciones en el cromosoma 22q11.2. Tomando como punto cardinal la cardiopatía congénita, se diseñó una estrategia para tamización y diagnóstico de SD22q11 con énfasis en la evaluación inmune. Es imprescindible realizar una historia clínica detallada y, posteriormente, un análisis cuantitativo y funcional de las subpoblaciones de linfocitos en sangre periférica para clasificarlo en SD22q11 completo (<1%) o parcial (95-99%) e instaurar las pautas de tratamiento en aspectos como: aislamiento del paciente, vacunación, profilaxis contra microorganismos oportunistas, uso de productos sanguíneos irradiados y reconstitución inmunológica. Sin embargo, el abordaje del paciente debe ser multidisciplinario para detectar y prevenir complicaciones a largo plazo que pueden ser graves, especialmente en los pacientes con SD22q11 completo.

In humans, 22q11 deletion syndrome (22q11DS) is considered the most common chromosome deletion syndrome. It is characterised by a clinical triad that includes congenital heart disease, hypocalcaemia and primary immunodeficiency. Approximately 85-90% of patients with this syndrome exhibit microdeletions in chromosome 22q11.2. Using congenital heart disease as a starting point, we designed a strategy for the screening and diagnosis of 22q11DS with an emphasis on immunological evaluation. A detailed clinical history and the subsequent quantitative and functional analyses of the lymphocyte subpopulations in the peripheral blood is crucial to classify as complete (<1%) or partial (95-99%) the disease and to guide clinicians in terms of patient isolation, vaccination, prophylaxis for opportunistic infections, use of irradiated blood products and immunological reconstitution. However, multidisciplinary care is necessary to detect and prevent long-term complications that could be severe, particularly in cases of complete 22q11DS.

Epilepsy and Other Neuropsychiatric Manifestations in Children and Adolescents with 22q11.2 Deletion Syndrome

BACKGROUND AND PURPOSE: 22q11.2 deletion syndrome (22q11.2DS) is the most common microdeletion syndrome. Epilepsy and other neuropsychiatric (NP) manifestations of this genetic syndrome are not uncommon, but they are also not well-understood. We sought to identify the characteristics of epilepsy and other associated NP manifestations in patients with 22q11.2DS. METHODS: We retrospectively analyzed the medical records of 145 child and adolescent patients (72 males and 73 females) with genetically diagnosed 22q11.2DS. The clinical data included seizures, growth chart, psychological reports, development characteristics, school performance, other clinical manifestations, and laboratory findings. RESULTS: Of the 145 patients with 22q11.2DS, 22 (15.2%) had epileptic seizures, 15 (10.3%) had developmental delay, and 5 (3.4%) had a psychiatric illness. Twelve patients with epilepsy were classified as genetic epilepsy whereas the remaining were classified as structural, including three with malformations of cortical development. Patients with epilepsy were more likely to display developmental delay (odds ratio=3.98; 95% confidence interval=1.5-10.5; p=0.005), and developmental delay was more common in patients with structural epilepsy than in those with genetic epilepsy. CONCLUSIONS: Patients with 22q11.2DS have a high risk of epilepsy, which in these cases is closely related to other NP manifestations. This implies that this specific genetic locus is critically linked to neurodevelopment and epileptogenesis.

Linkage and Association Analyses of Schizophrenia with Genetic Variations on Chromosome 22q11 in Koreans

OBJECTIVE: Chromosome 22q11 has been implicated as a susceptibility locus of schizophrenia. It also contains various candidate genes for which evidence of association with schizophrenia has been reported. To determine whether genetic variations in chromosome 22q11 are associated with schizophrenia in Koreans, we performed a linkage analysis and case-control association study. METHODS: Three microsatellite markers within a region of 4.35 Mb on 22q11 were genotyped for 47 multiplex schizophrenia families, and a non-parametric linkage analysis was applied. The association analysis was done with 227 unrelated patients and 292 normal controls. For 39 single nucleotide polymorphisms (SNPs) spanning a 1.4 Mb region (33 kb interval) containing four candidate schizophrenia genes (DGCR, COMT, PRODH and ZDHHC8), allele frequencies were estimated in pooled DNA samples. RESULTS: No significant linkage was found at any of the three microsatellite markers in single and multi-point analyses. Five SNPs showed suggestive evidence of association (p<0.05) and two more SNPs showed a trend for association (p<0.1) in pooled DNA association analysis. Individual genotyping was performed for those seven SNPs and four more intragenic SNPs. In this second analysis, all of the 11 SNPs individually genotyped did not show significant association. CONCLUSION: The present study suggests that genetic variations on chromosome 22q11 may not play a major role in Korean schizophrenia patients. Inadequate sample size, densities of genetic markers and differences between location of genetic markers of linkage and association can contribute to an explanation of the negative results of this study.

Phelan-McDermid syndrome presenting with developmental delays and facial dysmorphisms / 소아과

Phelan-McDermid syndrome is a rare genetic disorder caused by the terminal or interstitial deletion of the chromosome 22q13.3. Patients with this syndrome usually have global developmental delay, hypotonia, and speech delays. Several putative genes such as the SHANK3, RAB, RABL2B, and IB2 are responsible for the neurological features. This study describes the clinical features and outcomes of Korean patients with Phelan-McDermid syndrome. Two patients showing global developmental delay, hypotonia, and speech delay were diagnosed with Phelan-McDermid syndrome via chromosome analysis, fluorescent in situ hybridization, and multiplex ligation-dependent probe amplification analysis. Brain magnetic resonance imaging of Patients 1 and 2 showed delayed myelination and severe communicating hydrocephalus, respectively. Electroencephalography in patient 2 showed high amplitude spike discharges from the left frontotemporoparietal area, but neither patient developed seizures. Kidney ultrasonography of both the patients revealed multicystic kidney disease and pelviectasis, respectively. Patient 2 experienced recurrent respiratory infections, and chest computed tomography findings demonstrated laryngotracheomalacia and bronchial narrowing. He subsequently died because of heart failure after a ventriculoperitoneal shunt operation at 5 months of age. Patient 1, who is currently 20 months old, has been undergoing rehabilitation therapy. However, global developmental delay was noted, as determines using the Korean Infant and Child Development test, the Denver developmental test, and the Bayley developmental test. This report describes the clinical features, outcomes, and molecular genetic characteristics of two Korean patients with Phelan-McDermid syndrome.

Early onset intellectual disability in chromosome 22q11.2 deletion syndrome / Inicio temprano de discapacidad intelectual en el Síndrome de deleción del cromosoma 22q11.2

Chromosome 22q11.2 deletion syndrome, or DiGeorge syndrome, or velocardiofacial syndrome, is one of the most common multiple anomaly syndromes in humans. This syndrome is commonly caused by a microdelection from chromosome 22 at band q11.2. Although this genetic disorder may reflect several clinical abnormalities and different degrees of organ commitment, the clinical features that have driven the greatest amount of attention are behavioral and developmental features, because individuals with 22q11.2 deletion syndrome have a 30-fold risk of developing schizophrenia. There are differing opinions about the cognitive development, and commonly a cognitive decline rather than an early onset intellectual disability has been observed. We report a case of 22q11.2 deletion syndrome with both early assessment of mild intellectual disabilities and tetralogy of Fallot as the only physic manifestation.

El síndrome del cromosoma 22q11.2, también conocido como supresión o síndrome de DiGeorge o síndrome velocardiofacial, es uno de los síndromes más comunes de anomalías múltiples en los seres humanos. Este síndrome es comúnmente causado por una microdeleción del cromosoma 22 en q11.2 banda. Aunque este trastorno genético muestra varias anomalías clínicas y diferentes grados de compromiso orgánico, las características clínicas que han atraído la mayor atención son el comportamiento y el desarrollo, porque las personas con síndrome de deleción 22q11.2 tienen un riesgo 30 veces mayor de desarrollar esquizofrenia. Hay diferentes opiniones sobre el desarrollo cognitivo, y comúnmente se se ha observado un deterioro cognitivo en lugar de un inicio temprano de discapacidad intelectual. Presentamos un caso de síndrome de deleción 22q11.2 tanto con la evaluación temprana de discapacidades intelectuales leves como con la tetralogía de Fallot como única manifestación física.

El síndrome 22q11.2D S como un subtipo genético de esquizofrenia / 22q11.2 DS Syndrome as a Genetic Subtype of Schizophrenia

Introducción: El síndrome de deleción 22q11.2 (22q11.2 DS) se produce por microdeleciones del brazo largo del cromosoma 22 en la región q11.2. Después del síndrome de Down, es el segundo síndrome genético más común. En pacientes con esquizofrenia, el 22q11.2 DS tiene una prevalencia del 2%, mientras que en personas con esquizofrenia seleccionadas por características físicas específicas, aumenta un 32-53%. Objetivo: Describir las generalidades del 22q11.2 DS, sus características clínicas, los aspectos genético-moleculares y la frecuencia de la microdeleción de 22q11.2 en diferentes poblaciones. Métodos: Se hizo una revisión desde 1967 hasta 2013 en bases de datos de publicaciones científicas, orientada a recopilar artículos sobre el 22q11.2 DS y su relación con la esquizofrenia. Resultados: El 22q11.2 DS es una entidad genética que se asocia a un fenotipo variable relacionado con defectos congénitos en diferentes tejidos y órganos, así como a una alta frecuencia de trastornos psiquiátricos, particularmente la esquizofrenia. Se ha identificado alta prevalencia en grupos de personas con esquizofrenia seleccionadas por características sindrómicas comunes, como dificultades de aprendizaje, rasgos faciales típicos, anomalías palatales y defectos cardiacos congénitos. Las técnicas de FISH, qPCR, MLPA y, recientemente, aCGH y NGS se están usando para diagnosticar esta microdeleción. Conclusiones: En la práctica clínica es importante tener presente que las personas con 22q11.2 DS tienen alto riesgo de sufrir esquizofrenia, ya que la región 22q11.2 alberga genes candidatos relacionados con vulnerabilidad a esquizofrenia. Se considera que la concomitancia de esta enfermedad y 22q11.2 DS representa un subtipo genético de esquizofrenia. y métodos citogenéticos y moleculares para diagnosticar a este grupo de pacientes y optimizar un abordaje multidisciplinario en su seguimiento.

Introduction: The 22q11.2 deletion syndrome (22q11.2 DS) is associated with the microdeletion of this chromosomal region, and represents the second most common genetic syndrome after Down's syndrome. In patients with schizophrenia, 22q11.2 DS has a prevalence of 2%, and in selected groups can be increased to between 32-53%. Objective: To describe the generalities of 22q11.2 DS syndrome as a genetic subtype of schizophrenia, its clinical characteristics, molecular genetic aspects, and frequency in different populations. Methods: A review was performed from 1967 to 2013 in scientific databases, compiling articles about 22q11.2 DS syndrome and its association with schizophrenia. Results: The 22q11.2 DS syndrome has a variable phenotype associated with other genetic syndromes, birth defects in many tissues and organs, and a high rate of psychiatric disorders, particularly schizophrenia. Likewise, it has been identified in clinical populations with schizophrenia selected by the presence of common syndromic characteristics. FISH, qPCR and MLPA techniques, and recently, aCGH and NGS technologies, are being used to diagnose this microdeletion. Conclusions: It is important in clinical practice to remember that people suffering the 22q11.2 DS have a high genetic risk for developing schizophrenia, and it is considered that the simultaneous presence of this disease and 22q11.2 DS represents a genetic subtype of schizophrenia. There are clear phenotypic criteria, molecular and cytogenetic methods to diagnose this group of patients, and to optimize a multidisciplinary approach in their monitoring.